Product Announcement from Andover Corporation
Andover's Infrared Neutral Density (ND) filters are spectrally flat from 2-14µm. They are comprised of metallic coatings on high-quality Germanium substrates.
Metallic-coated ND filters obtain their optical density from a metal alloy coating on a substrate determined by the wavelength region of interest. Unlike the all-dielectric or absorption type, the metallic type ND filter employs a combination of absorption and reflection to reduce the intensity of light.
Andover has recently added more options to its already large stock selection. Custom sizes as well as threaded ring mounts are also available.